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        <h2>
          <span class="refentrytitle">hrtfearly</span>
        </h2>
        <p>hrtfearly — 
      Generates 3D binaural audio with high-fidelity early reflections in a parametric room using a Phase Truncation algorithm.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp114210096"></a>
        <h2>Description</h2>
        <p>
      This opcode essentially nests the <a class="link" href="hrtfmove.html" title="hrtfmove"><em class="citetitle">hrtfmove</em></a> opcode in an image model for a user-definable shoebox-shaped room. A default room can be selected, or advanced room parameters can be used. Room surfaces can be controlled with high and low-frequency absorption coefficients and gain factors of a three-band equaliser.
    </p>
        <p>
      Although valid as a stand alone opcode, <span class="emphasis"><em>hrtfearly</em></span> is designed to work with <a class="link" href="hrtfreverb.html" title="hrtfreverb"><em class="citetitle">hrtfreverb</em></a> to provide spatially accurate, dynamic binaural reverberation. A number of sources can be processed dynamically using a number of <span class="emphasis"><em>hrtfearly</em></span> instances. All can then be processed with one instance of <a class="link" href="hrtfreverb.html" title="hrtfreverb"><em class="citetitle">hrtfreverb</em></a>.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp114215792"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">aleft, aright, irt60low, irt60high, imfp <span class="command"><strong>hrtfearly</strong></span> asrc, ksrcx, ksrcy, ksrcz, klstnrx, klstnry, klstnrz, \
      ifilel, ifiler, idefroom [,ifade, isr, iorder, ithreed, kheadrot, iroomx, iroomy, iroomz, iwallhigh, \
      iwalllow, iwallgain1, iwallgain2, iwallgain3, ifloorhigh, ifloorlow, ifloorgain1, ifloorgain2, \
      ifloorgain3, iceilinghigh, iceilinglow, iceilinggain1, iceilinggain2, iceilinggain3]</pre>
      </div>
      <div class="refsect1">
        <a id="idp114218368"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>ifilel</em></span> - left HRTF spectral data file.
    </p>
        <p>
      <span class="emphasis"><em>ifiler</em></span> - right HRTF spectral data file.
    </p>
        <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
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                <img alt="[Note]" src="images/note.png" />
              </td>
              <th align="left">Note</th>
            </tr>
            <tr>
              <td align="left" valign="top">
                <p>Spectral datafiles (based on the MIT HRTF database) are available in 3 different sampling rates: 44.1, 48 and 96 kHz and are labelled accordingly. Input and processing <span class="emphasis"><em>sr</em></span> should match datafile <span class="emphasis"><em>sr</em></span>. Files should be in the current directory or the SADIR (see <a class="link" href="CommandEnvironment.html" title="Csound Environment Variables"><em class="citetitle">Environment Variables</em></a>).
      </p>
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                <img alt="[Note]" src="images/note.png" />
              </td>
              <th align="left">Note</th>
            </tr>
            <tr>
              <td align="left" valign="top">
                <p>HRTF Data files for use with 
      <a class="link" href="hrtfmove.html" title="hrtfmove"><em class="citetitle">hrtfmove</em></a>,
      <a class="link" href="hrtfmove2.html" title="hrtfmove2"><em class="citetitle">hrtfmove2</em></a>,
      <a class="link" href="hrtfstat.html" title="hrtfstat"><em class="citetitle">hrtfstat</em></a>,
      <a class="link" href="hrtfearly.html" title="hrtfearly"><em class="citetitle">hrtfearly</em></a>,
      <a class="link" href="hrtfreverb.html" title="hrtfreverb"><em class="citetitle">hrtfreverb</em></a>
       were updated for Csound 5.15 and later (the code was updated and is more efficient). Old datafiles are now deprecated.
      </p>
              </td>
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        <p>
      <span class="emphasis"><em>idefroom</em></span> - default room, medium (1: 10*10*3), small (2: 3*4*3) or large (3: 20*25*7). Wall details (high coef, low coef, gain1, gain2, gain3): .3, .1, .75, .95, .9. Floor: .6, .1, .95, .6, .35. Ceiling: .2, .1, 1, 1, 1. If 0 is entered, optional room parameters will be read.   
    </p>
        <p>
      <span class="emphasis"><em>ifade</em></span> - optional, number of processing buffers for phase change crossfade (default 8). Legal range is 1-24. See <a class="link" href="hrtfmove.html" title="hrtfmove"><em class="citetitle">hrtfmove</em></a>.
    </p>
        <p>
<span class="emphasis"><em>isr</em></span> - optional, default 44.1kHz, legal values: 44100, 48000 and 96000.
 </p>
        <p>
      <span class="emphasis"><em>iorder</em></span> - optional, order of images processed: higher order: more reflections. Defaults to 1, legal range: 0-4.
  </p>
        <p>
      <span class="emphasis"><em>ithreed</em></span> - optional, process image sources in three dimensions (1) or two (0: default).
  </p>
        <p>
      <span class="emphasis"><em>iroomx</em></span> - optional, x room size in metres, will be read if no valid default room is entered (all below parameters behave similarly). Minimum room size is 2*2*2.
  </p>
        <p>
      <span class="emphasis"><em>iroomy</em></span> - optional, y room size.
  </p>
        <p>
      <span class="emphasis"><em>iroomz</em></span> - optional, z room size.
  </p>
        <p>
      <span class="emphasis"><em>iwallhigh</em></span> - optional, high frequency wall absorption coefficient (all 4 walls are assumed identical). Absorption coefficients will affect reverb time output. 
  </p>
        <p>
      <span class="emphasis"><em>iwalllow</em></span> - optional, low frequency wall absorption coefficient.
  </p>
        <p>
      <span class="emphasis"><em>iwallgain1</em></span> - optional, gain on filter centred at 250 Hz (all filters have a Q implying 4 octaves).
  </p>
        <p>
      <span class="emphasis"><em>iwallgain2</em></span> - optional, as above, centred on 1000 Hz.
  </p>
        <p>
      <span class="emphasis"><em>iwallgain3</em></span> - optional, as above, centred on 4000 Hz.
  </p>
        <p>
      <span class="emphasis"><em>ifloorhigh, ifloorlow, ifloorgain1, ifloorgain2, ifloorgain3
</em></span> - as above for floor.
  </p>
        <p>
      <span class="emphasis"><em>
iceilinghigh, iceilinglow, iceilinggain1, iceilinggain2, iceilinggain3
</em></span> - as above for ceiling.
  </p>
        <p>
      <span class="emphasis"><em>ksrcx</em></span>  source x location, must be 10 cm inside room. Also, near-field HRTFs are not processed, so source will not change spatially within a 45 cm radius of the listener. These restrictions also apply to location parameters below. 
    </p>
        <p>
      <span class="emphasis"><em>ksrcy</em></span>  source y location.
    </p>
        <p>
      <span class="emphasis"><em>ksrcz</em></span>  source z location.
    </p>
        <p>
      <span class="emphasis"><em>klstnrx, klstnry, klstnrz</em></span>  listener location, as above.
    </p>
        <p>
      <span class="emphasis"><em>kheadrot</em></span> - optional, angular value for head rotation. 
    </p>
        <p>
      <span class="emphasis"><em>asrc</em></span> - Input/source signal.
    </p>
        <p>
      <span class="emphasis"><em>irt60low</em></span> - suggested low frequency reverb time for later binaural reverb.
    </p>
        <p>
      <span class="emphasis"><em>irt60high</em></span> - as above, for high frequency.
    </p>
        <p>
      <span class="emphasis"><em>imfp</em></span> - mean free path of room, to be used with later reverb. 
    </p>
      </div>
      <div class="refsect1">
        <a id="idp114252864"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the hrtfearly and hrtfreverb opcodes. It uses the file <a class="ulink" href="examples/hrtfearly.csd" target="_top"><em class="citetitle">hrtfearly.csd</em></a>. 
    </p>
        <div class="example">
          <a id="idp114254864"></a>
          <p class="title">
            <strong>Example 369. Example of the htrfearly opcode.</strong>
          </p>
          <div class="example-contents">
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>

<span class="comment">; Select flags here</span>
<span class="comment">; realtime audio out</span>
 -o dac
<span class="comment">; file ouput </span>
<span class="comment">; -o hrtf.wav</span>
  
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">nchnls</span> <span class="op">=</span> 2

gasrc <span class="opc">init</span> 0	<span class="comment">;global</span>

<span class="oblock">instr</span> 1		<span class="comment">;a plucked string, distorted and filtered</span>

  iamp <span class="op">=</span> 15000
  icps <span class="op">=</span> <span class="opc">cpspch</span>(p4)

  a1 <span class="opc">pluck</span> iamp, icps, icps, 0, 1
  adist <span class="opc">distort1</span> a1, 10, .5, 0, 0
  afilt <span class="opc">moogvcf2</span> adist, 8000, .5 
  aout <span class="opc">linen</span> afilt, 0, p3, .01
  
  gasrc <span class="op">=</span> gasrc <span class="op">+</span> aout

<span class="oblock">endin</span>

<span class="oblock">instr</span> 10	<span class="comment">;uses output from instr1 as source</span>
  
  <span class="comment">;simple path for source</span>
  kx <span class="opc">line</span> 2, p3, 9

  <span class="comment">;early reflections, room default 1</span>
  aearlyl,aearlyr, irt60low, irt60high, imfp <span class="opc">hrtfearly</span> gasrc, kx, 5, 1, 5, 1, 1, "hrtf<span class="op">-</span>44100<span class="op">-</span>left.dat", "hrtf<span class="op">-</span>44100<span class="op">-</span>right.dat", 1

  <span class="comment">;later reverb, uses outputs from above</span>
  arevl, arevr, idel <span class="opc">hrtfreverb</span> gasrc, irt60low, irt60high, "hrtf<span class="op">-</span>44100<span class="op">-</span>left.dat", "hrtf<span class="op">-</span>44100<span class="op">-</span>right.dat", 44100, imfp

  <span class="comment">;delayed and scaled</span>
  alatel <span class="opc">delay</span> arevl <span class="op">*</span> .1, idel
  alater <span class="opc">delay</span> arevr <span class="op">*</span> .1, idel

  <span class="opc">outs</span>	aearlyl <span class="op">+</span> alatel, aearlyr <span class="op">+</span> alater
  
  gasrc <span class="op">=</span> 0

<span class="oblock">endin</span>
  
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Play Instrument 1: a simple arpeggio</span>
<span class="stamnt">i</span>1 0 .2 8.00 
<span class="stamnt">i</span>1 + .2 8.04
<span class="stamnt">i</span>1 + .2 8.07
<span class="stamnt">i</span>1 + .2 8.11
<span class="stamnt">i</span>1 + .2 9.02
<span class="stamnt">i</span>1 + 1.5 8.11
<span class="stamnt">i</span>1 + 1.5 8.07
<span class="stamnt">i</span>1 + 1.5 8.04
<span class="stamnt">i</span>1 + 1.5 8.00
<span class="stamnt">i</span>1 + 1.5 7.09
<span class="stamnt">i</span>1 + 4 8.00

<span class="comment">; Play Instrument 10 for 13 seconds.</span>
<span class="stamnt">i</span>10 0 13

<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <br class="example-break" />
      </div>
      <div class="refsect1">
        <a id="idp114256656"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="hrtfreverb.html" title="hrtfreverb"><em class="citetitle">hrtfreverb</em></a>
      <a class="link" href="hrtfmove.html" title="hrtfmove"><em class="citetitle">hrtfmove</em></a>,
      <a class="link" href="hrtfmove2.html" title="hrtfmove2"><em class="citetitle">hrtfmove2</em></a>,
      <a class="link" href="hrtfstat.html" title="hrtfstat"><em class="citetitle">hrtfstat</em></a>,
      <a class="link" href="hrtfer.html" title="hrtfer"><em class="citetitle">hrtfer</em></a>.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp114262592"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: Brian Carty</td>
          </tr>
          <tr>
            <td>Maynooth</td>
          </tr>
          <tr>
            <td>2011</td>
          </tr>
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